apsidal
|ap-sid-al|
🇺🇸
/ˈæpsɪdəl/
🇬🇧
/ˈæpsɪd(ə)l/
relating to an apse or apsis
Etymology
'apsidal' originates from Late Latin 'apsidalis', ultimately from Latin 'apsis' and Greek 'hapsis', where the root meant 'arch' or 'vault'.
'hapsis' (Greek) passed into Latin as 'apsis' (Late Latin/Medieval Latin), which produced Late Latin adjective 'apsidalis'; from this formation English developed the adjective 'apsidal' (via Medieval/modern usage referring to church architecture).
Initially it referred to an 'arch' or 'arch-shaped recess' (the apse); over time it came to mean 'relating to an apse' in architecture and was later extended in technical contexts (astronomy/orbital mechanics) to mean 'relating to an apsis or line of apsides'.
Meanings by Part of Speech
Adjective 1
relating to or resembling an apse — a semicircular or polygonal recess, especially at the east end of a church; forming or having an apse.
The medieval cathedral features an apsidal choir that faces east.
Synonyms
Adjective 2
relating to an apsis or the line of apsides in orbital mechanics; used of motions or positions associated with periapsis and apoapsis (e.g., apsidal precession).
Astronomers measured the apsidal motion of the binary star system.
Synonyms
Last updated: 2025/09/28 17:02